Index: generic/tlsInt.h
==================================================================
--- generic/tlsInt.h
+++ generic/tlsInt.h
@@ -164,12 +164,11 @@
 # else
 #   define TCL_UNUSED(T) T JOIN(dummy, __LINE__)
 # endif
 #endif
 
-#if (TCL_MAJOR_VERSION < 9) && defined(TCL_MINOR_VERSION) && (TCL_MINOR_VERSION < 7) && !defined(Tcl_Size)
-#   define Tcl_Size int
+#if (TCL_MAJOR_VERSION < 9) && defined(TCL_MINOR_VERSION) && (TCL_MINOR_VERSION < 7) && !defined(TCL_SIZE_MODIFIER)
 #   define TCL_SIZE_MODIFIER ""
 #endif
 
 /*
  * Forward declarations